Ordered polymers are polymers having an "ordered" orientation in space i.e., linear, circular, star shaped, or the like, imposed thereon by the nature of the monomer units making up the polymer. Most ordered polymers possess a linear "order" due to the linear nature of the monomeric repeating units which comprise the polymeric chain. Linear ordered polymers are also known as "rod-like" polymers.
For example, U.S. Pat. No. 4,423,202 to Choe, discloses a process for the production of para-ordered, aromatic heterocyclic polymers having an average molecular weight in the range of from about 10,000 to 30,000.
U.S. Pat. No. 4,377,546 to Helminiak, discloses a process for the preparation of composite films prepared from para-ordered, rod-like, aromatic, heterocyclic polymers embedded in an amorphous heterocyclic system.
U.S. Pat. Nos. 4,323,493 and 4,321,357 to Keske et al., disclose melt prepared, ordered, linear, crystalline injection moldable polymers containing aliphatic, cycloaliphatic and araliphatic moieties.
U.S. Pat. No, 4,229,566 to Evers et al., describes para-ordered aromatic heterocyclic polymers characterized by the presence of diphenoxybenzene "swivel" sections in the polymer chain.
U.S. Pat. No. 4,207,407 to Helminiak et al., discloses composite films prepared from a para-ordered, rod-like aromatic heterocyclic polymer admixed with a flexible, coil-like amorphous heterocyclic polymer.
U.S. Pat. No. 4,108,835 to Arnold et al., describes para-ordered aromatic heterocyclic polymers containing pendant phenyl groups along the polymer chain backbone.
U.S. Pat. No. 4,051,108 to Helminiak et al., discloses a process for the preparation of films and coatings from para-ordered aromatic heterocyclic polymers.
Ordered polymer solutions in polyphosphoric acids (including PBT compositions) useful as a dope in the production of polymeric fibers and films are described in U.S. Pat. Nos. 4,533,692, 4,533,693 and 4,533,724 (to Wolfe et al.).
The disclosures of each of the above described patents are incorporated herein by reference.
Molecular orientation can be achieved during rotating die extrusion of thermoplastic polymers but the degree thereof is very low since random coil thermoplastic melts are not oriented to any great extent by shear, unless the melts are anisotropic. Minimal biaxial orientation of thermoplastics is obtained by blowing tubular films of the melt. Even then, the preferential molecular orientation in blown thermoplastic films is in the machine direction.
On the other hand, anisotropic dopes of ordered, rigid-rod polymers contain isolated bundles of oriented molecules suspended in solvent. Counter-rotating tubular extrusion of these polymers orients these crystallites in the direction of shear and stretching of biaxially-oriented tubular films of anisotropic dope by blowing further increases the degree of orientation in such materials. This is described in copending application Ser. No. 06/780,648, which is hereby incorporated by reference.